Removable disk cartridges for storing digital electronic information typically comprise an outer casing or shell that houses a magnetic, magneto-optical or optical disk upon which electronic information can be stored. The cartridge shell often comprises upper and lower halves that are joined together to house the disk. The disk is mounted on a hub that rotates freely within the cartridge. When the cartridge is inserted into a disk drive, a spindle motor in the drive engages with the disk hub in order to rotate the disk within the cartridge at a given speed. The outer shell of the cartridge typically has an aperture near one edge to provide the recording heads of the drive with access to the disk. A shutter or door mechanism is often provided to cover the aperture when the cartridge is not in use to prevent dust or other contaminants from entering the cartridge and settling on the recording surface of the disk.
Removable disk cartridges are often carried in cases by users, and are also often sold in cases to protect the cartridge during shipment, etc. Prior art cartridge cases do not provide sufficient protection against crushing. For example, typical prior art cartridge cases have flat cardboard inserts that provide stiffness for the top and bottom surfaces of the cartridge case, but do not provide a means of protecting the contents from crushing. Accordingly, there is a need for a crush resistant cartridge case. The present invention satisfies this need.